Roller-mill.



GEORGE BRIDDON AND ROBERT JOHN FOWLER, OF MANCHESTER, ENGLAND.

ROLLER-MILL.

Specification of Letters Patent.

Patented March 10, 1908.

Application filed January 10, 1907. Serial No. 351,714.

To all whom it may concern:

Be it known that we, GEORGE BRIDDON and ROBERT JOHN FOWLEE, subjects ofthe King of Great Britain and Ireland, and residents of Manchester, inthe county of Lancaster, England, flour-milling engineers, have inventedcertain new and useful Improvements in Roller-Mills, of which thefollowing is a specification.

This invention relates to improvements in roller mills used for crushingWheat or other granular substances but specially to such machines knownas break rolls in flour mills. The object of the break rolls, as thename implies, is to break down the wheat grains so that the bran,semolina, middlings, dunst and flour can be afterwards separated bymachines commonly employed for the purpose.

Prior to the date of our invention roller mills have been used in whichthe rolls, arranged in pairs, have either had their aXes in the samehorizontal or vertical plane or in a plane at an angle to thehorizontal. Where the axes are in the same horizontal plane the largergranules along with the smaller ones, or Hour, descend to the bottom ofthe machine in a practically continuous stream inwhich the severalclasses of products are fairly evenly intermixed. In mills, however, inwhich the axes are in a vertical or inclined plane the broken productsin passing from the rollers are, due to velocity im arted to them by thespeed at which the rol s revolve, thrown some distance from the point ofcontact of the rolls, according to their specific gravity, the heaviestbeing .thrown the farthest and the lightest the least distance and thusbecome se arated. Separation is also further effectedp by theapplication of air currents. It should, however, be understood thatwhile this separation is eEected in the manner aforesaid 1t has neverbeen taken advantage of hitherto since all the granules againcometogether at the bottom of the hopper which gathers them for the purposeof conveying to separators as hereinefore described.

NOW it is the obj ect of our invention to retain the natural separationof the several classes of products as hereinbefore referred to in rollermills having the axes of the rollers in a vertical or inclined plane andto' revent their coming together again at the ottom of the mill.

`Our invention thereforeconsists in providing roller mills of the typereferred to with means to kee the granules separat-ed, after beingcrushefFor broken by the rolls.

Our invention will be fully described with reference to the accompanyingdrawing which indicates a sectional elevation of amodern roller millconstructed in accordance with our invention.

The invention may be carried out in several Ways but in generall themeans employed for so carrying it out are of an extremely simple thoughimportant character.

In the drawing a represents the ordinary framework of the machine, b thepassages or spouts down which the material drops to the roller carranged at the top of the hoppers d, the grain passing from theselatter 'down inclined planes e to the break rolls f which are ofordinary construction and Which may be arranged with their axes g in aninclined plane as represented or in a vertical plane. h represents theusual air conduit and fi, removable panels to enable the interior of themill to be reached when required.A All these parts are of ordinaryconstruction 5 but in carrying out our invention we effect our object ofretaining separation of the broken materials passed through the rollersf by placing a partition, or partitions y' across the roller mill andpreferably parallel with a plane passing through the axes of the breakrolls between the adjacent edges of two or more streams of differentsized granules, that is to say the upper edge of each partition isadapted to separate tWo separate streams of granules.

The partitions may vary in number according to the character of theseparation required to be effected and the partitions may be liXed asindicated by broken lines and continued down to the base of the `rollermill, their lower edges being located immediately above a plurality ofcollecting troughs each adapted to convey away the separated product.Each of these troughs may be constructed in a manner well known inconnection with flour milling, and the several troughs, spouts,passages, conduits or the like may conduct the separated material to anysuitable place in the flour mill or to another roller mill or mchine inwhich still finer separation of the broken products may be obtainedeither in a similar manner to that described or by any of the usualmethods or machines employed.

The partition or partitions j may be stopped off at a convenient pointor curved leo 'their upper edges may be set to divide the severalstreams of granules in any desired manner. Any suitable means ofadjustment may be provided either located internally or externally ofthe machine frame e.

In the drawings we have shown the partitions each divided into two partsand pivoted to the sides of the machine frame a at 7. The partitions maybe moved about their centers 7c either towards or from the rolls asindicated by broken lines at the left hand side of the drawing andeither to retain the same width of space between the partitions or toincrease or decrease it. The partitions generally may also be arrangedat any required distance apart from each other as circumstances maydictate. The means for adjustment may be of any suitable and simpletype.

It will be readily seen that as the wheat l becomes crushed or broken inpassing through the break rolls it is thrown on the discharge side bycentrifugal force a greater or less distance away from the nip of therollers. Thus the larger granules fall into the farthest space m thenext larger into space It the next smaller into space o while theremainder falls into space p. The latter is practically flour and beingextremely light is carried partly round the lower roller more or less inthe manner `indicated at the left hand side of the drawing.

le would have it understood that while we employ partitions foreffecting and retaining the granules in a separate condition afterbreaking we may employ in conjunction with the partitions an air currentor currents to assist in the separation of the products as they aredischarged from the rolls. This air current, or currents, may be inducedinto the roller 4mill by suction from the air conduit 7L at any pointfound most suitable for effecting the object we have in view. Forinstance, we may fit in the frames t' gauze q through which the currentof air may be drawn in the direction of the arrows to the air conduit7L. Or we may provide a hole or holes in the frame. The air willtherefore pass over the upper edges of the partitions j, under theconduit cover 1 and so to the conduit 7b. In this way the various sizesof granules are directed to their proper spaces m, n, o or p. The aircurrent is induced through conduit h by any suitable fan or airexhausting device in connection with it.

The character of the air current may be varied by arranging the sides ofthe conduit cover r to be adjustable, their lower portions being pivotedat t as indicated in. the drawing the broken' lines showing the mannerof adjusting the air inlet a with relation to the conduit t. The cover 1may be hinged in one or in several pieces in their length. To pre* ventthe possibility of the air current ascending the spaces m, n, e, p,owing to the usual valves or slides in .any of the conveying spoutsbeing left open and so interfering with the separation of the brokenproducts as aforesaid we arrange pivoted valves w at the bottom of thespaces as indicated at the left hand side of the drawing, such valvebeing normally pressed against the opposite partition by springs or thelike the pressure of which can be overcome as required by the weight ofthe separated products passing down the spaces between the partitions,

By means of our invention we may entirely dispense with some of themachines at present used for separating the broken materials as theyusually leave the roller mill.

What we claim as our invention and desire to secure by Letters Patent isz An improvement in roller flour mills, consisting in means forel'l'ecting and retaining the separation of the broken products afterleaving the break rollers comprising in combination with a casing, anair conduit arranged vertically of the easing, a plurality of partitionsfor dividing the separated products positioned on opposite sides ol theconduit, each of said partitions having a section pivoted to the upperedge thereof movable to either side, valves located between thepartitions, a cover positioned above the air conduit, and sectionspivotally secured. to the cover adjustable with relation to the airconduit, said easing having openings adjacent the upper edges of thepartitions.

ln testimony whereof we hereunto set our hands in the presence of twowitnesses.

GEORGE BRIDDON. ROBERT JOHN FOWLER. litnesses: f

ILLIAM W. TAYLOR, ERNALD SmrsoN MosELEY.

